Devices for braking a reel-holder flange in rotating motion in textile apparatus have already been provided in the art. They comprise essentially a fixed flange connected to the arm supporting the reel, a first and a second braking shoe in the form of arched shells, coplanar and facing one in respect of the other, with external arched lateral faces which define a braking surface, and which are attached to said fixed flange, and means for driving the movement of said first and second braking shoe towards and against an annular band of said reel-holder flange arranged inside said braking shoes, to engage it with friction and to brake rotation of said reel-holder flange. Suitable elastic means are also provided to return, acting in opposition to said means for driving the braking action, said first and second shoe into a rest position of non-braking.
Braking devices for reel-holder flanges currently in use generally adopt braking shoes, of the type referred above, which are both restrained to said fixed flange at one of their facing or matching ends by means of a pin which allows outward rotation, driven by a suitable thrust device acting to move the shoes apart on the side opposite that of hinging.
Such a type of drive of the braking shoes is disadvantageous in that it brings into contact with the annular surface used for the braking action of said reel-holder flange only restricted portions of the external braking face of each shoe. This leads to low efficiency braking which rapidly consumes the shoes at the points in contact with the annular band of braking of the mobile flange.
Moreover said known braking devices, due to the fact that they have to attach said braking shoes one to the other and to said fixed flange and due to the fact that they often make use, to move the shoes apart, of mechanical thrust means which have a certain structural complexity, are awkward to set up and involve an excessive use of time for their assembly. Moreover in the field of textile apparatus, the need has been felt to provide braking assemblies for reel-holder flanges which are simple, inexpensive, compact and which can be actuated by means of a pressurised fluid. More particularly they have a thin section in order not to create excessive volume between the reel-holder flange and the support arm.
The object of the present invention is therefore that of providing a braking assembly for a reel-holder flange in textile apparatus which has a more effective braking action and longer-lasting life span of the parts in contact through friction compared to similar braking devices already known in the textile industry.
Another object of the present invention is that of providing a braking assembly for a reel-holder flange which, in addition to achieving the previous objects, occupies a limited volume, can be easily and rapidly prepared, involves low manufacturing costs and can be actuated by means of a pressurised fluid normally used for driving other components of the textile machine.